Starr Global Optimality Test    package:accuracy    R Documentation

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_D_e_s_c_r_i_p_t_i_o_n:

     Implements the Starr test for identification of the global optimum
     of a likelihood surface.

_U_s_a_g_e:

      starr(betas, tol=.0001, dmethod="euclidean")

_A_r_g_u_m_e_n_t_s:

   betas: Vector of parameter values

     tol: Tolerance distance between two parameter vectors to consider
          as "unique" optimum

 dmethod: method used to compute distance between two parameter vectors

_D_e_t_a_i_l_s:

     \texttt{starr} computes the probability that a local optimum,
     which may or may not be the global optimum, of a likelihood
     function has not been observed.  The probability is generated by
     counting the observed number of ``basins of attraction'' -
     starting values that lead to an local optimum.

_V_a_l_u_e:

     \texttt{starr} is a class "double" with value equal to the
     probability than a local optimum is unobserved.

_N_o_t_e:

     \texttt{starr} is given a vector of \texttt{betas} parameter
     values identifying local optima resultant of a search algorithm,
     such as \texttt{mle} or \texttt{nls}.  The starting values used to
     generate \texttt{betas} can be a grid, or for larger n-dimenional
     parameter spaces, may be randomly chosen.  The parameter values
     identifying a local optimum are passed to \texttt{starr} for each
     set of starting values that lead to that local optimum.

_A_u_t_h_o_r(_s):

     Micah Altman Micah_Altman@harvard.edu <URL:
     http://www.hmdc.harvard.edu/micah_altman/> , Michael McDonald

_R_e_f_e_r_e_n_c_e_s:

     Altman, M., J. Gill and M. P. McDonald.  2003.  _Numerical Issues
     in Statistical Computing for the Social Scientist_.  John Wiley &
     Sons. <URL: http://www.hmdc.harvard.edu/numerical_issues/>

     Finch, S. J., Mendell, N. R., Thode, H. C., Jr. 1989.
     ``Probabilistic Measures of Adequacy of a Numerical Search for a
     Global Maximum.'' _Journal of the American Statistical
     Association_ {\bf 84}, 1020-3.

     Starr, N. 1979. ``Linear Estimation of the Probability of
     Discovering a New Species.'' _Annals of Statistics_ {\bf 7},
     644-52.

